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1.
JPC – Journal of Planar Chromatography – Modern TLC - A new high-performance thin-layer chromatographic (HPTLC)—densitometric method which can be employed in the routine analysis... 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - A simple, rapid, quantitative, and validated high-performance thin-layer chromatographic (HPTLC) method has been developed for the... 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - Piperine is the most important alkaloid molecule present in Piper nigrum. In this study, a simple, rapid, quantitative... 相似文献
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High-performance thin-layer chromatography‒mass spectrometry (HPTLC‒MS) method was developed for the estimation of epimers (+)-catechin (CA) and (‒)-epicatechin (ECA) in Onosma bracteatum Wall. Resolving these epimers is challenging and so method optimization was done for the selection of the stationary phase and the mobile phase to achieve their coherent separation. To further increase the reliability of the obtained densitometric results, HPTLC–MS analysis was performed. The genus Onosma L. is a species-rich genus that exhibits complex patterns of morphological and karyological diversity, and highly debatable taxonomic approaches. Thus, many similar species are described based on morphological differences and often quite ambiguous. To facilitate the identification of O. bracteatum, separation was achieved using pre-coated silica gel 60 F254 HPTLC plate as the stationary phase and a mixture of diisopropyl ether–ethyl acetate–formic acid (9.0:0.2:0.7, V/V) as the mobile phase for the separation of epimers CA and ECA. Sample preparation, mobile phase selection and optimization were given importance to manage good resolution (RF) of these markers. Flavan-3-ols CA and ECA were identified and confirmed on the basis of RF and in situ UV and MS overlaid spectra with respective standards. The method was validated for linearity, inter-day precision, intra-day precision, repeatability, accuracy, specificity, limit of detection, and limit of quantification. The average recoveries for epimers CA and ECA from ethyl acetate extract fraction (MEF) were found 98.86 and 99.03% indicating the good reproducibility for each marker. The proposed validated HPTLC method is simple, accurate and reproducible and is the first report on the separation and quantification of the epimers CA and ECA in O. bracteatum using HPTLC–MS. 相似文献
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Cilnidipine is a calcium channel blocker that is used to treat cardiac diseases such as angina and high blood pressure. Several column and planar chromatographic methods for estimating cilnidipine in pharmaceutical dosage forms have been documented. However, these method developments have been carried out employing organic solvents such as acetonitrile, methanol, toluene, chloroform, and others as mobile phase components or as sample pretreatment diluents. These organic solvents are neurotoxic and teratogenic to humans and aquatic animals, according to International Council for Harmonization Q3C (R8) recommendations. According to the green analytical chemistry approach, such organic solvents should be reduced or removed during the development of chromatographic methods for environmental protection and the safety of human and aquatic animal life. As a result, the stability-indicating chromatographic estimation of cilnidipine was performed utilizing less toxic organic solvents. To prevent organic solvent waste during method development, mobile-phase optimization was performed using the design of experiment-based response surface modeling. Cilnidipine has been subjected to hydrolysis, oxidation, photolysis, and dry-heat decomposition to determine its stability. The greenness profiles of the suggested and published chromatographic methods were examined using the national environment method index, analytical greenness calculator, green analytical procedure index software, and eco-scale assessment tool. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - The purpose of this study was to qualitatively and quantitatively analyze cynaroside (CYN), apiin (API), diosmin (DIO), and linarin... 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - The present study was carried out for screening an efficient extraction method and extracting solvent in different plant parts of... 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - Drug development from medicinal plants by using various hydroalcoholic solvents has been an emerging trend in the last few decades.... 相似文献
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An improved normal phase high performance liquid chromatographic (NP-HPLC) method was developed for simultaneous quantification of eight vitamin E isomers (α-, β-, γ- and δ-tocopherols and α-, β-, γ- and δ-tocotrienols) and γ-oryzanol in rice. A complete separation of all compounds was achieved within 25 min using an Inertsil CN-3, SIL-100A 5 μM (4.6 mm × 250 mm) column and an isocratic elution system of hexane/isopropanol/ethylacetate/acetic acid (97.6:0.8:0.8:0.8, v/v/v/v) at a flow rate varying from 0.7 to 1.5 mL min(-1). A linear correlation coefficient (r(2)>0.99) and high reproducibility were obtained at concentrations ranging 0.05-10 μg mL(-1) for vitamin E isomers and 0.5-500 μg mL(-1) for γ-oryzanol. This method proved to be rapid, accurate and reproducible. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - In the present investigation, a simple and effective high-performance thin-layer chromatography (HPTLC) method was developed and... 相似文献
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Summary A new method has been developed for the HPLC determination of the activity of lactase from the microorganisms in yoghurt. The method is based upon the ability of -galactosidase to hydrolyze lactose bonds in glucose and galactose. To determine such activity in yoghurt, 1 mL of yoghurt was diluted 110 with 0.1 M phosphate buffer (pH 7) containing 2 % ( w/v) lactose and 5 mM dithioerythritol as reducing agent; the mixture was the incubated and injected into the HPLC. Lactase activity remained high as long as the number of viable microorganisms did not fall below the minimum CFU·mL –1 (10 7). This method is more repeatable than conventional colorimetric determination, and may also be automated for routine analysis. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - The aim of this study was to identify and quantitatively determine kaempferol, quercetin, and gallic acid in the... 相似文献
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The development of an analytical method for the determination of four selected pyrethroid insecticides at residue level in beef meat is presented. Acetone and petroleum ether at 40-60 degrees C were chosen as extraction solvents. A two-step clean-up was performed using an Extrelut NT3-C(18) system followed by a Florisil column, with disposable, ready-to-use cartridges. Instrumental analysis was carried out on a gas chromatograph equipped with an electron capture detector (GC-ECD), using matrix-matched and internal standard calibration techniques. Confirmatory analysis by GC-MS was performed. Recoveries at the EU Maximum Residue Limit (MRL), 0.5 x MRL and 1.5 x MRL levels and the repeatabilities were widely satisfactory. The main advantage of the method was the reduction of analysis time as compared with previously published works. The applicability of the method to different matrices and pesticide classes will be investigated. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - Dantrolene sodium (DAN) is widely used as a muscle relaxant drug for the treatment of malignant hyperthermia.... 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - The separation and estimation of natural products by chromatographic techniques such as high-performance liquid chromatography... 相似文献
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A validated high-performance thin-layer chromatography (HPTLC) method was developed for the simultaneous quantification of oleanolic acid, β-sitosterol and lupeol in the bulb of Urginea indica Kunth. Separation of metabolites was done in mobile phase using toluene‒ethyl acetate‒methanol‒acetone (7:2:0.2:0.2, V/V) and quantification was done after derivatization by dipping in aninsaldehyde‒sulphuric acid; densitometric scan was performed at 530 nm. The proposed method for quantification was linearly calibrated in the range of 200‒1000 ng/spot for oleanolic acid and β-sitosterol; 100‒500 ng/spot for lupeol, and it was found specific and repeatable. The RF values were found at 0.44 ± 0.03, 0.55 ± 0.05 and 0.68 ± 0.08, limit of detection and limit of quantification were 1.045, 0.524, 0.525 µg/spot and 3.167, 1.588, 1.592 µg/spot for oleanolic acid, β-sitosterol and lupeol, respectively. Precision and recovery study for sample and standards were within the limit of the International Council for Harmonization guidelines. Oleanolic acid, β-sitosterol and lupeol were found to be 0.113%, 0.105% and 0.036%, respectively, in methanolic extract of plant on dry weight basis. This study will help in checking routine quality control of herbal drugs as well as herbal formulations containing U. indica. 相似文献
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Biochars obtained by biomass pyrolysis have been proposed as a soil amendment to improve soil properties and fertility as well as to retain pesticides and other environmental contaminants. The present study investigates the degradation of metribuzin herbicide and its metabolites deamino- (DA), deaminodiketo- (DADK) and diketo- (DK) metribuzin under simulated solar light and dark conditions as well as their mobility using TLC plates coated with soil and soil?biochar mixtures at 1% and 5% w/w ratio. Biochar was characterised by X-Ray diffraction, porosimetry, scanning electron microscopy and Fourier transform infrared spectroscopy. Degradation under light conditions followed biphasic kinetics, with bi-exponential model fitted better for the soil substrate, while the Gustafson–Holden model was found more appropriate to describe degradation kinetics in 1% soil/biochar mixture. In soil, DA presented the lowest degradation rate (DT 50:440.9 h), followed by metribuzin (DT 50:208.0 h), DADK (DT 50:110.8 h) and DK (DT 50:106.5 h). The addition of biochar reduced drastically the degradation or even inhibited the photolytic process for the studied reaction period. The mobility retention factor (Rf) in soil ranged from 0.49 for metribuzin to 0.63 for DADK. The addition of biochar practically immobilises the compounds in the surface layer as R f ranged from 0.14 to 0.10 for metribuzin and from 0.23 to 0.16 for DADK in soil/biochar mixtures 1% and 5%, respectively. In conclusion, the addition of biochar reduced dramatically the photodegradation rates as well as the mobility of metribuzin and its metabolites due to increased adsorption. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
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Himalaya PartySmart capsule is a polyherbal formulation recommended for its liver-protective properties. As the formulation contains extracts of six different herbs, a large number of markers are present in the same. This research work reports the standardization of Himalaya PartySmart capsule using andrographolide and catechin as therapeutic phytoconstituents to assess its quality and efficacy. A specific, sensitive, precise, and accurate high-performance thin-layer chromatography (HPTLC) method has been developed for the quantitative estimation of andrographolide and catechin. Separation was performed on TLC silica gel 60 F254 aluminum plates as the stationary phase using chloroform‒acetone‒formic acid (7:3:0.5, V/V) as the mobile phase with densitometric detection at 259 nm. The developed method was validated as per the recommendations of the International Council for Harmonisation (ICH) Q2(R1) guideline. Each marker phytoconstituent showed a good linear relationship with an average correlation coefficient (r2) = 0.99 in the concentration range studied. The proposed method was found to be specific, precise, and accurate with recovery within the range of 95‒105% and hence can be used for the routine analysis of PartySmart capsule formulation. 相似文献
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